Step 1
Shut off the power to the microwave from your home's main circuit breaker box. Push the breaker switch that supplies the electricity to the appliance to the "Off" position for the duration of your repairs.
Step 2
Remove the screws securing the air grille above the microwave door; the type and number of screws varies by brand and model. Pull the grille off of the front of the appliance and set it aside.
Step 3
Open the microwave door. Remove the hinge pin or screw holding the door assembly to the top hinge. Lift the door assembly up and off of the bottom hinge. Place the removed door face down on a padded surface.
Step 4
Clean the hinge areas with a sponge and warm, soapy water to remove any grime or food particles. Dry the hinges with a soft cloth. A buildup of food or grime on the hinges may prevent them from opening and closing properly.
Step 5
Try gently wiggling the door hinges. Tighten the hinge screws along the top and bottom edges of the microwave cabinet if you felt the hinges move.
Step 6
Replace the door hinges if they are bent or broken. Remove the hinge screws from the top and bottom edges of the microwave cabinet. Keep the removed screws, but discard the old hinges. Line up the screw holes on the cabinet with the mounting screw holes on the replacement hinges. Reinsert and tighten the removed screws.
Step 7
Reverse the disassembly process to replace the microwave door. Flip the breaker switch back to the "On" position to restore the electrical supply.